Jacketed projectile and method of applying the jacket to the core



Jan. 26, 1943. R. J. soUTHwELL ET AL 2,309,360

JACKETED PROJECTILE AND METHOD OF APPLYING THE JACKET TO THE CORE Filed Jan. 2, 1941 INVENTO R5 /PqYMo/vo J' Scarf/WHL "A M ATTO R N EY OFFICE JACKETED PROJECTILE lli APPLYING THE .IAT T i on or rm: com:

Application .lanuary 2, 1941, Serial No. 372,768

8 Claims. (Cl. ,Z9-1.23)

This invention relates to jacketed projectiles and the method of applying the jacket to the core of the projectile.

One of the objects of the invention is an improved jacketed projectile more particularly of the type comprising a steel core and a jacket of softer metal, such as copper or nickel or the like, and to provide such core with a continuous one piece imperforate jacket in intimate contact with every point on the surface of the core.

Another object of the invention consists in providing a core with a jacket consisting of one piece of metal with which the rear end of the jacket about the rear end of the core is continuous metallically and imperforate and in which the pointed end of the core is provided with a line of cleavage or pipe in front of the penetrating point of the core.

Another object of the invention consists in an improved method of applying a jacket to a core and more particularly in applying a jacket having a rear closed end to a core and in intimate contact with every point on the surface of the core. f

Other objects of the invention will appear from the following description taken in connection with the drawing in which- Fig. l shows a cup or blank from which the jacket is made;

Fig. 2 shows in longitudinal section a blank y after it has been reduced on a mandrel to the diameter of the core and to conform to the shape of the boat tail end of the core;

Fig. 3 shows the core inserted in the jacket;

Fig. 4 shows the core and jacket about to be pushed through a die to seat the boat tail end of the core against the end of the jacket and to compress the walls of the jacket into intimate contact with the surface of the body of the core;

Fig. 5 shows the core and jacket after they have been pushed through the die in Fig. 4;

Fig. 6 shows the jacket after it has been closed about the penetrating point of the core by a metal owing operation; and

Fig. 7 shows the jacketed core forced through a qualifying die.

In Fig. 1 is shown a cup or jacket blank l0 or copper or other suitable soft metal which is preferably made by any well known drawing operation and which is of larger interior diameter than that oi the core of steel or other suitable metal to be jacketed and which is of such length and of such wall thickness as to provide sufiicient material so that a part of the wall may be thickened Vto t the boat tail end of the core and the length of the blank may be increased to provide sulcient metal to close the open end of the jacket about the penetrating point of the core and to provide for the proper contour of the point of the jacket.

As disclosed in Fig. 2 the cup disclosed in Fig. 1 is placed over a mandrel ll which isnf the same diameter as that of the body of the core l2 and is provided with a frusto-conical end as indicated at I3 of the same shape and diameter as the frusto-conical boat tail end it of th., core. The cup l0 is then reduced in diameter upon the mandrel' Il by a metal llowing operation as by means of radially movable dies to produce the blank I5 disclosed inFig. 2 Whose main body portion has an interior diameter substantially the same as that oi the body portion of the core It and whose closed end is provided with an interior seat I6 of the same taper and diameter as the boat tail end l0 of the core. In this operation the length of the blank is increased to substantially the length of the core and the Wall thickness is decreased as appears from Fig. 2. The open end of the blank l5 is then squared and cut to the length in relation to the core indicated in Fig. 3.

The core is then inserted in the blank I5 with a substantially close t as indicated in Fig. 3.

The assembled jacket blank and core are then pushed through a die 20 by means of a pusher 2| provided with a conical recess 22 in its end tting the conical surface of the penetrating point 23 of the core. The end of the pusher 2l is also provided with a cylindrical recess 20 to receive the extreme end 25 of the penetrating point of the core to prevent injury thereto. The die 20 is of such diameter as to construct the jacket blank into intimate contact with the outer surface of the core and rcause the boat tail end I0 of the core to seat against the closed end i6 of the jacket blank.

Fig. 4 shows the jacket blank and core at the beginning of this operation and Fig. 5 shows the jacket blank and core at the end of this operation as the jacket blank leaves the die. In this operation the length of the jacket blank l5 is but slightly increased as is apparent by comparing Fig. 5 with Fig. 4.

In the next operation as disclosed in Fig. 6 the open end ofthe jacket blank is closed about the penetrating point 23 of the core in a metal ilowing machine of the type including radially movable dies indicated at 2t, 20. These dies move radially inwardly and outwardly, are relatively rotatable with respect to the jacketw-blank and flow the metal oi` the end of the jacket blank about and into intimatecontact with the penetrating point of the core to produce the completed jacket vil@ shown in Fig. 6. It will be noted that enough metal is provided to iorm a K etration of the metal of the jacket as in the usual construction in which the pointed end of the -jacket is the closed end of the jacket made by the usual drawing operation. It will be noted that as the pointed end of the jacket is made by flow-forming it upon the penetrating point of the core it will closely t the penetrating point of the core and it will not be necessary to use a ball oi lead or the like to adapt the point of the jacket to the penetrating point of the core. It will also be noted that every point of the inner wail of the jacket is in intimate contact with the outer face of the core and that there is no opening of any sort through which explosive gas could enter between the jacket and the core which might expand the jacket as it is passing through the rifle or expand the same an-d distort or rip it after the projectile has left the bore of the rifle which would greatly interfere with the correct'travel of the projectile.

As disclosed in Fig. 7 as the last step in this operation the jacketed core is pushed point first through a qualifying die 35 by means of a squared end pusher tt which nally sizes the jacket, insures that the ymain body or the jacket is in intimate contact with the main body of the core and also squares up the closed end of the jacket as indicated at tl.

The advantages of the invention may be comprehended when it is explained that in constructions now in use the jacket is formed with a pointed end to receive the penetrating point of the core and it is the practice to place a small ball of lead between the penetrating point of the core and the jacket, and then to close the open rear end of the jacket about a disc placed against the rear end of the core so as to prevent gases of explosion from entering the jacket. This operation of closing the rear end of the jacket forces the core farther into the Jacket and distorts the ball of lead to iill the space between the penetrating point of the core and the point of the jacket which are difficult to t when they are made and assembled in accordance with the old method. It has been found that this old method does not always eect a gas tight engagement of the jacket with the disc and that gases of explosion have entered the jacket and ripped the jacket from the projectile as it left the bore of the gun or rifle which caused the projectile to divert from its normal course. By means of this invention, no gases of explosion can enter the jacket wall as the rear end of the jacket is an integral part of the body of the jacket and moreover there is a close fit of the jacket on the core. If desired a ball of lead can aaoaaeo be placed against the point of the projectile and the jacket can be closed over the ball of lead by this method as is obvious.

We claim: Y

1. The method of jacketing a hard metal core provided with a penetrating point which consists in inserting the tail end of a core into and against the closed end of a soit metal jacket and in closing the open end of the jacket about the penetrating point of the core by a metal flowing operation.

2. The method of jacketing a hard metal core provided with a penetrating point which consists in inserting the tail end of a core into and against the closed end of a soft metal jacket and in closing the open end of the jacket about the penetrating point of the core by radially directed metal iiowing operations.

3. The method of jacketing a hard metal core provided with a penetrating point which consists in inserting the tail end of a core into and against the closed end of a soft metal jacket and in closing the open end of the jacket about the penetrating point of the core by radially directed metal working impacts.

4. 'Ihe method of jacketing a hard metal core having a boat tail end and a penetrating point which consists in providing a soft metal jacket having a closed end with a conical inner surface adjacent said closed end conforming to the boat tail end of the core and in closing the open end of the jacket about the penetrating point of the core by a metal working operation.

5. The method of jacketing a hard metal core which consists in inserting the core into a soft metal cup-shaped jacket blank having a rear closed end and in pushing the assembled core and jacket blank through a constricting die to constrict the jacket blank on the core.

6. 'I'he method of jacketing a hard metal core provided with a. penetrating point which consists in inserting the core into a soft metal cupshaped jacket blank having a rear closed end and in pushing the assembled core Aand jacket blank through a constricting die to constrict the jacket blank on the core and in closing the'open end of the jacket blank about the penetrating point of the core by a metal iiowing operation.

7. The method of jacketing a hard metal core provided with a penetrating point which consists in inserting the core into a soft metal cupshaped jacket blank having a rear closed end and in pushing the assembled core and jacket blank through a constricting die to constrict the jacket blank on the core and in closing the open end 0i the jacket blank about the penetrating point of the core by a metal flowing operation, leaving a line of cleavage in the jacket so formed extending axially of the core and the jacket.

8. -The method of jacketing a hard metal core provided with apenetrating point which consists in inserting the core into a soft metal cupshaped jacket blank having a rear closed end and in pushing the assembled core and jacket blank through a constricting die to constrict the jacket blank on the core, in closing the open end of the jacket blank about the penetrating point of the core by a metal owing operation, and in pushing the jacketed core pointed end rst through a qualifying die.

` RAYMOND J. SOUTHWELL.

EDWARD A. CQNNER. 

